1, The full form of UAC is User Account Control. It’s used on Computing ,Security in Worldwide

User Account Control (UAC) is a technology and security infrastructure introduced with Microsoft’s Windows Vista and Windows Server 2008 operating systems, with a more relaxed version also present in Windows 7 and Windows Server 2008 R2 . It aims to improve the security of Microsoft Windows by limiting application software to standard user privileges until an administrator authorizes an increase or elevation.

2, The full form of UAC is United American Committee. It’s used on Associations & Organizations ,Non-Profit Organizations in United States

The United American Committee (commonly called the UAC) is a non-partisan, non-profit, 501c(3) organization dedicated to educating the nation about the current threats that they believe are confronting the U.S., with the primarily focus on confronting Islamic extremism.